With respect, if the default backup directory for your instance doesn't exist, I'd suggest that's a misconfiguration issue rather than a limitation of the "backup database" command. I can think of a whole world of other things I could do with an instance that'd get perfectly valid SQL commands that'd work on a properly configured instance throwing up errors instead.

In the specific situation you've described, I'd personally amend your instance's backup path so it points to the new location you prefer to use.

Also with respect, I was not criticising the SQL command but, rather, pointing to the question having more than one correct answer.

It is debatable if moving your database files (including the Backup folder) away from the C: system drive is "misconfiguration".

Not changing the inane Microsoft default backup directory is more debatable - for the ones not brave enough to change the registry by hand, Phil Phactor has a 2 Kms DMO script and Vince Jacoboni one in Perl - see http://www.simple-talk.com/community/blogs/philfactor/archive/2007/03/22/21152.aspx.

I prefer to NEVER rely on default configured letters... but, then again, that was just a QOTD which IMHO it has more than one correct answer or requires more qualifying conditions.

Hmm. Despite efforts to the contrary, it seems I've managed to explain myself badly, and come across rather arrogantly at the same time. My apologies.

I don't think that changing storage locations, whether default or actual, around is in itself misconfiguration at all; my point was that making those changes but not telling SQL Server about the amendment may well qualify, despite the scenario you highlighted having very little impact. In this, I made an (unsafe) assumption that this is what you had done, since when I've edited the registry to point to another drive as the default backup location, it's worked fine, and the backup command has picked up the new default location.

Not the first time today that what I've said and what I've meant have been different, either. I think I might head back off to bed as soon as possible....

Well I did get the correct answer, and when I try it on a SQL 2005 server where the SQL excecutables are installed on O: and the databases are on D: the backup actually ran to the installation created backup folder on D:.